Sprites is completely black after using translucentlitspritematerial

Hello,

After using the translucentlitspritematerial for the background, so i can make some light. The background completely went to black.

Example:

The white-blue point is the light (It’s just for a test, since the 4.17 and so, doesn’t show light in orthographic camera). So ignore this. This is 4.15 And in Game Mode.

The problem is the background that completely went to black (This is the default background of the game). So what i want is to change it a little to normal but not a lot. How should i do it?

Thanks for the answer. Really appreciate this. This is one of the foundation of my game.
EDIT: I did create a material where i can change the colour for my custom background (Not the default one) but it’s still completely black but of course when i use light, it will show the picture and not completely black, but outside of the light’s range is still completely black).